The Cell Culture Media Preparation Facility (located in room 721 of the McArdle Laboratory) is under the faculty supervision of Dr. Janet Mertz. This 220 square foot facility is equipped with a laminar flow food, a water distillation apparatus, multiple filtration apparatuses, a balance, a pH meter, a 37 degree Celsius incubator, and several refrigerators. Ms. Kathy Johnson prepares and sterilizes cell culture media according to the needs of each investigator. Last year she prepared more than 3,800 liters of media; these media included DMEM with high glucose, Joklik, S-MEM, DMEM without phenol red, RPMI-1640 and F-12. Ms. Johnson also prepares special buffers and media such as DMEM lacking specific amino acids. She insures the sterility of each batch of medium by testing it for growth of contaminants and holding it for 3 to 4 weeks until all tests prove negative. During the last year, Ms. Johnson also prepared for bacterial and yeast work approximately 8,150 plates containing various nutrients, drugs, and indicators. These media are stored in 1/2 and 1 litter bottles in refrigerators located in room 721. Researchers throughout the McArdle Laboratory check out these media as needed, indicating the quantities taken so the costs of the ingredients can be charged back to the individual research groups.